LMX2320 National Semiconductor, LMX2320 Datasheet
LMX2320
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LMX2320 Summary of contents
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... The LMX2315 LMX2320 and the LMX2325 feature very low current consumption typically and 11 mA re- spectively The LMX2315 LMX2320 and the LMX2325 are available in a TSSOP 20-pin surface mount plastic package Block Diagram TRI-STATE is a registered trademark of National Semiconductor Corporation ...
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... Connection Diagrams 20-Lead (0 173 Wide) Thin Shrink Small Outline Package (TM) Order Number LMX2315TM LMX2315TMX LMX2325TM LMX2325TMX LMX2320TM or LMX2320TMX Pin Descriptions Pin No Pin Name OSC I Oscillator input A CMOS inverting gate input intended for connection to a crystal resonator for IN operation as an oscillator The input has a V ...
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... Functional Block Diagram Note 1 The prescalar for the LMX2315 and LMX2320 is either 128 129 while the prescalar for the LMX2325 Note 2 The power down function is gated by the charge pump to prevent unwanted frequency jumps Once the power down pin is brought low the part will go into ...
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... Power Supply Voltage Voltage on Any Pin with GND Storage Temperature Range ( Lead Temperature (T ) (solder 4 sec ) L Electrical Characteristics LMX2325 and LMX2320 Symbol Parameter I Power Supply Current CC I Power Down Current CC-PWDN f Maximum Operating Frequency IN f ...
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... Electrical Characteristics LMX2325 and LMX2320 except as specified (Continued Symbol Parameter I Charge Pump Output Current D o -source -sink I Charge Pump Output Current D o -source -sink I Charge Pump TRI-STATE Current D o -Tri Charge Pump Output Current ...
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... Typical Performance Characteristics LMX2320 Charge Pump Current vs D Voltage o Charge Pump Current Variation http www national com LMX2315 12339– 4 Charge Pump Current 12339– 40 Sink vs Source Mismatch 12339– 12339 – 51 ...
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... Voltage LMX2320 25 Input Sensitivity vs Frequency LMX2315 Input Sensitivity vs Frequency (Continued) Oscillator Input Sensitivity TL W 12339 – 5 LMX2320 25 Input Sensitivity vs Frequency TL W 12339 – 10 LMX2315 Input Sensitivity vs Frequency TL W 12339 – 12339– 12339– 12339– 42 ...
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... LMX2320 25 Input Sensitivity at 3V Temperature Variation 12339– 12 LMX2315 Input Sensitivity at 5V Temperature Variation 12339– 43 LMX2320 25 Input Impedance vs Frequency 12339– GHz Real GHz Real ...
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Charge Pump Current Specification Definitions I1 CP sink current sink current sink current ...
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... If the Control Bit (last bit input) is HIGH the DATA is transferred into the R Counter (programmable reference divider) and the S Latch (prescaler select LMX2315 and LMX2320 128 129 LMX2325 65) If the Control Bit (LSB) is LOW the DATA is transferred into the N Counter (programmable divider) ...
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Functional Description (Continued) PROGRAMMABLE DIVIDER (N COUNTER) The N counter consists of the 7-bit swallow counter (A counter) and the 11-bit programmable counter (B counter) If the Control Bit (last bit shifted into the Data Register) is LOW data is ...
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Functional Description (Continued) SERIAL DATA INPUT TIMING Notes Parenthesis data indicates programmable reference divider data Data shifted into register on clock rising edge Data is shifted in MSB first Test Conditions The Serial Data Input Timing is tested using a ...
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Analog Switch The analog switch is useful for radio systems that utilize a frequency scanning mode and a narrow band mode The purpose of the analog switch is to decrease the loop filter time constant allowing the VCO to adjust ...
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Typical Application Example Operational Notes VCO is assumed AC coupled R increases impedance so that VCO output power is provided to the load rather than the PLL Typical values are 10 IN level f RF impedance ranges from 40 to ...
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Application Information LOOP FILTER DESIGN A block diagram of the basic phase locked loop is shown FIGURE 1 Basic Charge Pump Phase Locked Loop An example of a passive loop filter configuration including the transfer function of the loop filter ...
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Application Information Therefore if we specify the loop bandwidth phase margin Equations 1 through 6 allow us to calcu- p late the two time constants T1 and T2 as shown in equa- tions 7 and 8 A common rule of ...
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Application Information (Continued) Consider the following application examples Example MHz V e VCO (Note 900 MHz e opt F 200 kHz e ref 4500 e e opt ref ...
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Application Information MEASUREMENT RESULTS (Example FIGURE 5 PLL Reference Spurs The reference spurious level is 74 dBc due to the loop k b filter attenuation and the low spurious noise level of the LMX2315 FIGURE 6 PLL Phase Noise 10 ...
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Application Information (Continued) Example MHz V e VCO (Note 1665 MHz e opt F 300 kHz e ref 5550 e e opt ref 2 20 kHz 1 ...
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... FIGURE 10 PLL Reference Spurs The reference spurious level is 65 dBc due to the loop k b filter attenuation and the low spurious noise level of the LMX2320 FIGURE 12 PLL Phase Noise 20 kHz Offset The phase noise level at 20 kHz offset is http www national com TL W 12339– 34 ...
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Application Information (Continued) EXTERNAL CHARGE PUMP The LMX PLLatinum series of frequency synthesizers are equipped with an internal balanced charge pump as well as outputs for driving an external charge pump Although the superior performance of NSC’s on board charge ...
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... Wide) Thin Shrink Small Outline Package (TM) Order Number LMX2315TM LMX2320TM or LMX2325TM For Tape and Reel Order Number LMX2315TMX LMX2320TMX or LMX2325TMX (2500 Units per Reel) LIFE SUPPORT POLICY NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT ...